1. Field of the Invention
The present invention relates to an image processing apparatus and a control method thereof.
2. Description of the Related Art
In conventional technologies, the brightness in a partial region of a video image is smoothed in accordance with the distribution of brightness (brightness distribution) within that region, to preserve thereby sufficient contrast in regions having a large brightness distribution, and suppress noise emphasis in regions having a small brightness distribution (flat region) (Japanese Patent Application Publication No. 2003-263637).
Moreover, a technique is employed whereby changes in γ-curve between regions is smoothed (Japanese Patent Application Publication No. 2008-263586) in technologies where a video image is divided into a plurality of regions (divisions), and gradation is adjusted for each region using a gradation conversion curve (γ-curve) according to the image, to enhance thereby the contrast ratio of the image.